1. Field of the Invention
This invention relates to a flashlight, more particularly to an improved variable focusing flashlight.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a conventional variable focusing flashlight includes a metal barrel (11) for receiving a cell unit (11') therein. The metal barrel (11) has an open end formed with an inwardly annular conductive flange (111), and a covering (14) formed with a metal compression spring (141) in contact with the cell unit (11'). A bulb support (12') includes a first insulating member (12) provided in the metal barrel (11) adjacent to the open end thereof. The first insulating member (12) includes a first base plate having a pair of opposite curved slots (123) and an annular peripheral flange extending from the first base plate. The bulb support (12') further includes a second insulating member (13). The second insulating member (13) includes a second base plate (131) and a pair of opposite curved plates (132) extending from the second base plate (131). The second base plate (131) is adapted to rest against the annular conductive flange (111). The curved plates (132) are inserted into the metal barrel (11) and fixedly engaged in the curved slots (123). A bulb (16) is mounted on the second base plate (131) and has two conductive plugs passing through the second base plates (131). The first insulating member (12) further includes an L-shaped first conductive member (121) mounted thereon and connected to one of the conductive plugs of the bulb (16), and a second conductive member (122) mounted thereon and connected to the other of the conductive plugs of the bulb (16) and to the cell unit (11'). A flashlight head (15) includes a tubular portion having an end formed with an engaging opening adapted to threadedly engage the metal barrel (11), and a concave reflector (151) fixed in the tubular portion having an enlarged open end and a constricted open end in contact with the second base plate (131). The bulb (16) is deactivated when the flashlight head (15) is rotated toward the metal barrel (11) so that the concave reflector (151) urges the second base plate (131) to rest against the annular conductive flange (111), thereby breaking electrical contact between the first conductive member (121) and the annular conductive flange (111). The bulb (16) is activated when the flashlight head (15) is rotated away from the metal barrel (11) so that the first conductive member (121) electrically contacts the annular conductive flange (111) by the metal compression spring (141) biasing the first insulating member (12) toward the annular conductive flange (111). The flashlight head (15) is rotated relative to the metal barrel (11) so as to vary the distance between the bulb (16) and the enlarged open end of the concave reflector (151) in order to adjust the focal distance of the light output of the bulb (16). The bulb support (12') is moved relative to the metal barrel (11) to activate and deactivate the bulb (16). The bulb support (12') easily sways and is positioned in an unstable manner, thereby affecting the conduction effect of the bulb (16).